Lead screw coupling



Patented May 4, i948 LEAD SCREW :olilLrriGy` Y l Leo Conroy, Waterloo, N. Y.

Application-April 25, 1945, seriaiNo. 590,187

The present invention relates to new andluseful improvements in couplingsof atype adapted for connecting lead screwsA to vworkhead spindles of threading lmachines and for various other purposes where an easily-manipulated coupling is desired for connecting male and female parts to each other. g

i An importantobject of the present invention is to provide a coupling of this character possessing certain definite advantages not possessed by other types of couplings and including the provision of a tapered seat in the spindle or female part in which a tapered stem on the male part, or lead screw, is seated and drawn in tight frictonal engagement by the nut without excessive strain on the nut, such tapering construction and the nut providing a tight joint between the parts and further providing an interlocking connection between the male and female parts to eliminate play at the joint thereof.

A further object of the invention is to provide a device of this character of simple and practical construction, which is ecient and reliable in operation, relatively inexpensive to manufacture, and otherwise well adapted for the purposes for which the same is intended.

Other objects and advantages reside in the details of construction and operation as more fully hereinafter described and claimed, reference being had to the accompanying drawing forming part hereof, wherein like numerals refer to like parts throughout, and in which:

Figure 1 is a longitudinal sectional view of the coupling.

Figure 2 is a transverse sectional view taken substantially on a line 2-'2 of Figure 1, and

Figure 3 is a detail of the locking plug for the ball bearings forming part of the coupling and with parts shown in section.

Referring now to the drawing in detail, wherein for the purpose of illustration I have disclosed a preferred embodiment of the invention, the numeral 5 designates a work head driving spindle which constitutes the female part of the coupling, the spindle being formed with a tapering bore 8.

'Ihe lead screw is designated at 1 and which forms the male part of the coupling, the inner end of the lead screw being formed with a. tapering stem 8 conformably received in the tapering bore 6 of the spindle.

The lead screw 1 is formed with a threaded portion 9 at the inner end of the stem 8 adapted for threaded engagement with the internally threaded portion I0 in one end of the bore II of a 2 Claims. (o1. 287-1055 couplingnut 'IZQmounted for free rotation on the outer end' of" the spindle 5.

The outer surface of the spindle 5 is provided with spaced circumferential grooves lIII and the 1 bore II ofthe nut I2 is formed `with a groove I3 adapted for selectively registering with grooves I4 and for receiving aplurality of ball bearings I5.

The ball bearings are inserted in the grooves through a lateral passage I6 in the nut I2 the passage being closed after the insertion of the ball bearings by means of a plug I 'I having a threaded head threaded in a countersink of the passage I6, the plug including a stem I8 having a recess or radius I 9 formed at its inner end to conform to the groove I3 of the nut and to receive the balls therein, the inner end of the plug thus forming part of the raceway for the balls.

One 'side of the stem I8 is formed with a recess 20 adapted for receiving the inner end of a locking pin 2 I, inserted in a passage 22 extending parallel to the axis of the nut and having a threaded outer end 23 for securing the pin locking engagement in the nut.

The outer end of the spindle 5 is formed with a recess 24 in which a dowel pin 25 is adapted for engagement, the dowel pin projecting laterally from the inner end of the stem 8.

The plurality of circumferentially extending longitudinally spaced raceways I3 and I4 in the nut and spindle provide means for adjustingl the nut I2 longitudinally on the spindle, the nut being freely rotatable on the spindle by means of the balls I5 seated in said grooves or raceways.

After the balls I5 have been placed in position in the grooves or raceways and secured therein by the plug I'I and locking pin '2I, the stem 8 of the lead screw I is then inserted in the spindle with the dowel Din 25 seated in the recess 24 to prevent relative rotation thereof andthe nut I2 is then threaded on the threaded portion 5 of the lead screw.

The tapered stem 8 is thus drawn tightly in the tapered bore 6 of the spindle and the parts thus coupled firmly to each other.

The outer periphery of the nut I2 is preferably knurled, as indicated at 26, and also formed with recesses 21 for receiving a Spanner wrench and the lead screw 1 may also be formed with an opening 28 for receiving a pin or Spanner wrench to hold the lead screw while the nut is being tightened.

In view of the foregoing description, taken in conjunction with the accompanying drawing, it is believed that a clear understanding of the construction, operation and advantages of the de- 'vice will be quite apparent to those skilled in the art. A more detailed description thereof is accordingly deemed unnecessary.

While the foregoing specification sets forth the invention in specific terms, it is to be understood that numerous changes in the shape, size and mawhat I male part having a threaded section, a nutIv adapted for engagement with said threadeol-apart.

said female part having an externaly annular groove and said nut having an internalannularf 20 Number groove and said nut having an internal annular groove adapted for registering with the groove of the female part, said nut having a. filler opening adapted for receiving balls for seating in said grooves for rotatably connecting the nut to the female part, a plug for said opening having a. concave recess in its inner end conforming to the groove of the nut in one position of the plug, said plug having a radial recess, and locking means in said? nutE for detaehabkvengaging; the radial recess tol retain`Y the concave recess "in alignment with the groove of the nut.

LEO J. CONROY.

REFERENCES CITED The following references are of record in the ii'lefoi?r this: patent y UNITED STATES PATENTS Name Date Hogam Sept; ,22g/,1891 Vl 241,829? Y- Heap ;Auga8;1922 13143059: Browns rAugnZawa 1,962,739' f Hoegger .Juneslizglr FoREIGNfPATENTs" Lf Country Date,-` f Switzerland... ApnA lf, .1932

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